294 RHODOPHYCEZ,, 
Famity IV. LEMANHACEA. 
Fluviatile alge. Thallus developed from a confervoid pro- 
thallic filament, setaceous, almost simple, hollow, nodose, having 
an internal and a cortical layer of cells. Polyspores numerous, 
collected in branched moniliform series, germinating without 
fertilization. 
Genus 121. LEMANEA. Bory. (1808.) 
The only genus in the family, with the same characters as above 
given. 
“The dilated portions of the threads are loosely filled with the spores, 
which are produced within the frond. The spores are oval, thick-walled 
cells, joined together to form series. which are very much branched, so 
that from acentral basal row they rise as a complex bush-like mass. The 
first step, according to Wartmann, in their germination, consistgin the 
elongation of the spore, and the projection of one end, which is soon cut 
off by the formation of @ transverse partition, and constitutes a new cell. 
This multiplication soon develops intoa branched confervoid filament. A 
large number of these filaments are generally produced in one place at 
one time, and form a very apparent greenish layer. Finally, certain cells 
in branches of these filaments swell up and become very much broader 
than their fellows, undergoing, at the same time, division so rapidly that 
they become very short. By-and-bye they divide also in the direction 
of their breadth, so that, instead of a simple series of cells, there arises 
acompound mass. This is the beginning of the new frond. At first it 
is dependent upon the parent filament, but soon acquires a root-like pro- 
cess at the base, and develops rapidly into the complex cartilaginous 
plant.”—Wartmann, Beitrage zur Lemanea (1854). 
Lemanea fluviatilis. Ag, Spec. Aig. u. p. 4. 
Simple, or sparingly branched, 3-4 inches long, straight, 
nodules rather remote, with about three verticillate papille. 
Size. Spores (04x °025 mm. 
Rabh. Alg. Eur. iii.,411. Kirch. Alg. Schles. 43. Eng. FI. v., 
p. 822.. Hook. FI. Scot. ii., 84. Eng. Bot. ii., t. 2423. Jenner 
Tunb. Wells 176. Harv. Man. 119. Johnst. Fl. Berw. ii, 
246. Mack. Hib. 220. Gray Arr.i., 288. Hass. Alg. 72. 
Lemanea corallina, Bory Ann. de Mus. xx., t. 21, f. 2. 
Conferva fluviatilis, Dill. Conf. t. 29. Hull Br. Fl. 332. 
Eng. Bot.i., t. 1763. Huds. Ang. ii.,597. With. Arr. iv,, 
184. Lightf. Fl. Scot. 985. 
Conferva fluviatilis lubrica setosa equiseti facie, Dill. Muse. 39, 
t. 7, f. 47. 
Nodularia fluviatilis, Grev. Fl. Ed. 8300. Fl. Devon. ii, 57. 
Attached to stones, wood, &c., in streams. 
